Devices for cleaning, polishing and finishing work pieces using vibrators and a suitable particulate media material are known in the art. For example, U.S. Pat. No. 3,422,577 describes a self-discharging vibratory mill with a weir over which media and workpieces are cascaded for discharge. U.S. Pat. No. 3,693,298 describes a vibrator finishing machine with an improved separating screen. An annular vibratory finishing bowl with a downwardly-directed discharge funnel is shown in U.S. Pat. No. 3,877,178. Other vibratory finishing machines are described and shown in U.S. Pat. Nos. 3,893,266, 4,067,147, 4.161,848, 4,184,290, 4,257,196, 4,693,037 and 4,301,625.
Bowls that are removably mounted on a mechanical vibrator to clean ammunition cases are known and have been available on the marketplace for some time.